[L., neut. sing. of ūnic-us UNIQUE a. So in G. and Du.] A unique example, specimen, or thing.

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1885.  Daily Tel., 14 July, 5/3. Some picture, work of art, or old book, which is represented to him as being a ‘unicum.’

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1892.  Mrs. J. P. Morgan, trans. Rubinstein’s Conv. on Music, 26. The symphony in G minor (this unicum of symphonic-lyric).

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